1. Field of the Invention
This invention generally relates to color photographic materials, and more particularly, to color photographic materials wherein the fading of dye images obtained and discoloring of uncolored portions (i.e., unexposed portions, hereinafter referred to as white ground) are prevented.
2. Description of the Prior Art
Color images obtained by processing silver halide color photographic material are generally composed of azomethine dyes or indoaniline dyes formed by the reaction of the oxidation product of an aromatic primary amine developing agent and couplers.
It is generally desirable that the color photographic images thus-obtained be preserved for a long period of time as a record or for exhibition, but these photographic images are not always stable to light and humidity, and hence when the color images are exposed to light for a long period of time, or preserved under conditions of high temperature and high humidity for a long period of time, fading or discoloring of the color images and discoloring of the white ground usually occurs, causing deterioration of the image quality.
Such fading or discoloring of images can be fatal defects in image recording materials. Certain compounds tending to overcome these difficulties have higherto been used. Examples include hydroquinone derivatives such as 2,5-di-tert-butylhydroquinone, etc.; phenol compounds such as 2,6-di-tert-butyl-p-cresol, 4,4'-methylenebis(2,6-di-tert-butylphenyl), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), 4,4'-isopropylidenediphenol, etc.; and compounds such as tocopherol, etc. Also, compounds formed by acylating or alkylating the hydroxy groups of these phenolic compounds, tocopherol compounds, and hydroquinone derivatives have recently been prepared.
These compounds may exhibit some effect for preventing the occurrence of fading or the discoloring of dye images, but these compounds also have disadvantages, in that the effect is low, or, if they have a strong effect for the prevention of fading, they adversely affect color hue, form fog, cause poor dispersion, and/or form crystals. Thus, dye image stabilizers which exhibit excellent properties in all photographic aspects have not yet been found.